1. Field of the Invention
This invention relates to hand tools and is particularly directed to a combination carpenters level and square.
2. Prior Art
In carpentry, it is customary to use a level to assure that a given structural member is truly plumb and level, after which a square is used to make certain that components attached to the first member are properly perpendicular to the first member. Usually, this is a two-step operation, in which the level is used first and, then, is set aside while the square is used. However, this requires that the carpenter purchase two tools. Furthermore, the first member sometimes will become dislocated while the exchange of tools is occurring, in which case, neither of the members will be correctly situated and the entire structure will be faulty. In order to overcome these problems, several combination level and square tools have been proposed heretofore. However, many of the prior art combination tools have been complex to construct and expensive to purchase. Furthermore, most of the prior art combination tools have provided levels as insets which are mounted in a square and which can become dislocated, if the tool is dropped, and will provide erroneous indications thereafter. Also, many of the level inserts of the prior art combination tools are small and difficult to read. Furthermore, while a level indicates whether or not a given member is plumb or level, it does not provide incremental information. Thus, a level may tell that a member is out of line, but it will not tell how far out of line the member is. Consequently, the carpenter must rely upon trial-and-error to correctly align the errant member. Unfortunately, the prior art combination tools have done nothing to overcome this deficiency. A search in the United States Patent office has revealed the following:
______________________________________ U.S. Pat. No. INVENTOR ISSUED ______________________________________ 2,728,989 C. J. Laggren Jan. 3, 1956 4,700,489 A. J. Vasile Oct. 20, 1987 4,944,096 S. D. Tolley Jul. 31, 1990 4,964,219 G. E. Clark Oct. 23, 1990 ______________________________________
Each of these references is subject to the deficiencies noted above. Thus, none of the prior art combination level and square tools have been entirely satisfactory.